Screenshot url change, website
Screenshot url change, website

* Screenshot is now linked on gh-pages (hopes it wil be fine on docker hub)
* website on gh-pages ready on http://epfl-sti.github.io/octave-x11-novnc-docker/
epfl-sti/octave-x11-novnc-docker,epfl-sti/octave-x11-novnc-docker,epfl-sti/octave-x11-novnc-docker,epfl-sti/octave-x11-novnc-docker,epfl-sti/octave-x11-novnc-docker,epfl-sti/octave-x11-novnc-docker